Missing PCIe interface in lspci - Kernel

This is a discussion on Missing PCIe interface in lspci - Kernel ; In the process of advising a user on getting a BCM4311 wireless device to work with bcm43xx rather
than ndiswrapper, the device stopped appearing in an lspci output. The 'lspci -vn' output
for this device before this failure was:
03:00.0 ...

Missing PCIe interface in lspci

In the process of advising a user on getting a BCM4311 wireless device to work with bcm43xx rather
than ndiswrapper, the device stopped appearing in an lspci output. The 'lspci -vn' output
for this device before this failure was:

Fortunately, the "customer" has two identical machines. Swapping the wireless cards showed that both
BCM4311s work in the other computer, but neither works in the problem machine. Kernel Version
2.6.22.4-65.fc7 is used on both.

Doing a line-by-line comparison of the dmesg outputs, the only thing that stands out is that the line

Allocate Port Service[0000:00:03.0cie03]

is missing on the faulty computer. This is the bridge that should connect to the device in question.

The BIOS has been reset and reflashed without helping the problem.

Is there anything other than some failure on the motherboard that would lead to this situation? Is
there anything that we can try? The BIOS in this machine doesn't have many options.